JPS5826359Y2 - Malfunction prevention device for automatic weighing label pasting machine - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a malfunction prevention device for an automatic weighing and labeling machine.

Generally, in automatic weighing and labeling machines, articles are sent onto a weighing conveyor using an incoming conveyor, where they are weighed using a scale, and then sent out on an outgoing conveyor for continuous weighing.

Therefore, if the scale comes into contact with a weighing conveyor or the like for some reason during this weighing, the operation of the scale, which enables accurate weighing, will not be stable.

However, conventional automatic weighing and labeling machines are manufactured so that the scale and conveyor do not come into contact with each other.
Since the operation is performed on the premise that this state will not go awry, even if the scale and the conveyor come into contact as described above, the weighing operation will still be performed, causing erroneous weighing.

This idea was developed in consideration of these points. When the scale is in contact with the conveyor, this state is electrically detected and the motor that drives the conveyor is stopped to prevent incorrect weighing. The object of the present invention is to obtain a malfunction prevention device for an automatic weighing and labeling machine.

In this invention, a conveyor driven by a motor and a scale for weighing articles conveyed by the conveyor are provided in close proximity, and conductive parts are provided in each of the conveyor and the scale, and whether these conductive parts are in contact or non-contact. The present invention is characterized in that it includes a motor control section that controls the operation of the motor depending on the contact state.

Therefore, when the scale and the conveyor come into contact, this is detected and the motor is stopped by the motor control section, making it impossible to measure unless the malfunctioning part is corrected, so that erroneous weighing can be prevented.

An embodiment of this invention will be explained based on the drawings.

1 is a conveyor, which is driven by a motor 2.

A scale 3 is provided adjacent to the conveyor 1.

Although the conveyor 1 and the scale 3 are shown conceptually, there are conductive parts 4,
5 is formed.

The motor 2 is connected to a series circuit including a power supply 6, a drive switch 11, a stop switch 8, a relay contact 9 which is a motor control section operated by a detection signal, and a coil relay 10, and the coil relay 10 is connected to the drive switch T. Self-holding relay contacts 11 are connected in parallel.

Therefore, the relay coil 9a provided with the relay contact 9
is connected to a transistor 15 in the output stage of transistors 13, 14, and 15 connected in three stages through a power supply circuit 12, and a Zener diode 16 is connected between the base of this transistor 150 and the collector of the transistor 14.

Further, the conductive portion 4 is connected to the base side of the first stage transistor 13 via a diode 4a, and the conductive portion 5 is connected to the collector side.

In such a configuration, when weighing articles continuously, first, the drive switch 7 is closed, and the electrically closed state is maintained by the coil relay 10 to drive the motor 2 and drive the conveyor 1.

At this time, the articles are sent onto the conveyor 1 by a carry-in conveyor (not shown), placed on the scale 3 at a predetermined timing, and weighed.

At this time, in a normal state where the conveyor 1 and the scale 3, that is, the conductive part 4.5 do not come into contact with each other, the transistor 13 is OFF and the transistor 1 is OFF in FIG.
4 is ON and the transistor 15 is OFF, the relay coil 9a also does not operate and the conveyor 1 continues to be driven, and the next articles are weighed one after another.

On the other hand, when the scale 3 and the conveyor 1 move relative to each other in the advancing direction or a direction perpendicular thereto due to some reason during weighing and come into contact, the conductive part 4 of the conveyor 1 and the conductive part 5 of the scale 3 When an abnormal state occurs in which the zener diode 1 contacts, the transistor 13 turns on and the transistor 14 turns off in the circuit shown in FIG.
6 becomes conductive, turning on transistor 15, and energizing relay coil 9a.

Therefore, the normally closed relay contact 9 opens and the motor 2 is connected in series to open the circuit, so the current to the coil relay 10 is cut off, and the relay contact 11 opens and loses its self-retention, causing the conveyor to move forward. Stop 1.

Therefore, the metering operation does not proceed any further and there is no possibility of erroneous metering.

At this point, you can inspect and repair the device and start the next measurement.

In this example, the casings of the conveyor 1 and the scale 3 are formed as conductive parts 4 and 5, but if the conveyor 1 and the scale 3 are made of insulators, conductive foil may be attached to them. It can also be used as a conductive part.

Further, the motor control section is not limited to the relay contact 9, but may be any one that controls the motor 2 based on the contact state of the conductive sections 4 and 5.

This device provides continuous weighing by providing conductive parts on the conveyor and scale as described above, and by providing a motor control part that controls the operation of the motor that drives the conveyor depending on the contact or non-contact state of these conductive parts. If the conveyor and scale come into contact, the conveyor will not stop and the weighing operation will not be interrupted; instead, the device can be inspected and repaired, and then restarted, thereby preventing incorrect weighing. Further, it has the effect of stabilizing the operation of the scale.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention; FIG. 1 is a layout diagram of a conveyor and a scale, FIG. 2 is a motor drive circuit diagram, and FIG. 3 is a circuit diagram of a motor control section.

Claims (1)

[Scope of utility model registration request] A conveyor driven by a motor and a scale for weighing articles conveyed by the conveyor are provided in close proximity, and conductive parts are provided on each of the conveyor and the scale, and the contact or non-contact state of these conductive parts causes the A malfunction prevention device for an automatic weighing label pasting machine, characterized in that it is provided with a motor control section that controls the operation of a motor.